Manufacturing method for manufacturing a cotton-containing product

ABSTRACT

In order to manufacture a cotton-containing product of a cotton material, when the cotton material is refined and bleached in the state of a sliver, heating is performed, with steam, on the cotton material with a chemical agent applied to the cotton material, and, when the heating is performed, the steam is applied to the cotton material in the state of a sliver sheet formed by arranging the sliver in a sheet shape.

TECHNICAL FIELD

The present invention relates to a manufacturing method for manufacturing a cotton-containing product.

BACKGROUND ART

In recent years, in the cotton agriculture, development and streamlining have been tried in, e.g., a cultivating method, or improvement, research and development of seeds, to increase the production of cotton. The basic material of produced cotton is fibers comprising cellulose, but it contains first impurities such as dirt and a minute amount of oil that adhere before it is harvested as a plant. Therefore, the color of cotton is not white but brownish. If these impurities remain, when dyeing a cotton product formed of cotton, the impurities repel the dye, thus making it difficult to dye the cotton product as desired.

Therefore, when processing fibers including cotton, it is necessary to dye the fibers after whitening the fibers by removing the above impurities. Specifically, a knitted cloth or a woven cloth is manufactured by using spun raw threads, and is refined and bleached in a dyeing factory equipped with discharged water treating facilities and water supply environment, thereby obtaining a greige before sewn.

Specifically, as a general method, spun threads formed into a “skein shape” are refined, bleached and dyed in a package dyeing machine or a hank dyeing machine, or spun threads formed into a “cheese shape” are refined, bleached and dyed in a package dyeing machine. In some cases, in order to reduce costs, refining and bleaching are performed in a package dyeing machine, and dyeing is performed in a hank dyeing machine.

When dyeing threads for jeans, a rope dyeing machine is often used with the threads bundled together. However, the threads are often refined and bleached in thread form by using a package dyeing machine.

For example, the below-identified Patent Document 1 proposes a processing method by which, when refining and bleaching a cotton cloth, second impurities applied in thread spinning, spinning, weaving, knitting steps are removed, too. The below-identified Patent Document 2 proposes a chemical agent treating method when performing glue removal and refining to fabrics. Also, in some cases, a method is used by which raw threads are refined and bleached in thread form, and then are kitted and woven, thereby obtaining a pre-sewn greige.

PRIOR ART DOCUMENT(S) Patent Document(s)

-   Patent document 1: Japanese Unexamined Patent Application     Publication No. 2002-238555 -   Patent document 2: Japanese Patent No. 5554172

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

However, a large amount of water resources is consumed in the above refining and bleaching steps. While, during the manufacturing steps of cotton products, including the dyeing step, a large amount of water resources is required and consumed, the amount of water resources used for bleaching and refining among these accounts for as high as 70 to 80% of the total amount of water resources used to manufacture cotton products. Since a huge amount of water resources is consumed to manufacture cotton products, there are many countries and regions where cotton products cannot be manufactured from home-grown cotton. This is one of the main reasons why the cotton textile industry is shifting from many countries where the cotton agriculture has developed to other developing countries.

However, in developing countries, a situation often occurs where water resources are not sufficiently purified after use. Therefore, manufacturing cotton products could lead to worsening of the environment of developing countries.

It is an object of the present invention to reduce the amount of water resources consumed when manufacturing cotton-containing products, thereby protecting the environment of the respective countries and thus the global environment.

Means for Solving the Problems

In order to achieve the above object, in the present invention, a cotton material is refined and bleached in the state of a sliver.

The “sliver” is an aggregate of fibers formed in a strip shape or a rope shape before twisting the cotton into threads. Since, in this sliver state, the individual fibers have not been entangled and have been separated compared to twisted threads, chemical agents and water used for refining and bleaching easily infiltrate into the individual fibers. Therefore, it is possible to significantly reduce the amount of consumed water compared to conventional methods in which twisted threads or fabrics are refined and bleached.

Also, in the present invention, when the refining and the bleaching are each performed in the sliver state, heating may be performed with steam. Since, in the sliver state, the individual fibers are exposed to the atmosphere, unlike twisted threads or fabrics, steam is easily applied to the individual fibers without being interrupted by the adjacent fibers. Therefore, after immersion in chemical agents used for refining and bleaching, the heating of the individual fibers with steam is smoothly performed without being hindered by the adjacent fibers, and can be easily performed at a high temperature to such an extent that the above chemical agents sufficiently act on the fibers. Also, since steam has a very low specific gravity compared to liquid water, compared to heating, in a hot water bath, for refining and bleaching, it is possible to significantly reduce the amount of consumed water resources by using steam for heating. Also, compared to conventional methods in which a hot water bath is used, and thus a large amount of water needs to be heated, since the mass of steam is significantly small compared to its volume, it is possible to significantly reduce the amount of energy required and consumed for heating with steam.

Also, in the present invention, when steam is applied to the sliver, the sliver may be refined and bleached while being arranged in a sheet shape. The sliver has not been twisted yet, but, if the sliver is gathered in a rod shape, it may be difficult to apply steam to the center of such a sliver. In contrast thereto, if the sliver is arranged in a sheet shape, all of the fibers constituting the sheet-shaped sliver are exposed, so that it is possible to save the amount of consumed steam and the amount of heat required for creating steam. Also, since slight friction is generated between the adjacent fibers of the sheet-shaped sliver, and the sheet-shaped sliver is kept wet by a chemical liquid, steam, etc., the sheet-shaped sliver can be sequentially processed as a continuous sliver sheet while being conveyed.

Also, in the present invention, after the sliver sheet is heated by applying steam to the sliver sheet, the sliver sheet may be washed while being conveyed by at least one perforated conveying medium. Since the sliver has not been twisted unlike threads, if the sliver is pulled strongly in its length direction, the sliver is likely to be separated, and thus it is difficult to convey the sliver while being pulled like threads. By washing the sliver while being placed on the at least one perforated conveying medium, it is possible to covey and wash the sliver constituting the sliver sheet, while applying little force to the sliver. The at least one perforated conveying medium may be, e.g., a mesh conveyor.

The following may be adopted: The at least one perforated conveying medium comprises two perforated conveying media comprising inner and outer mesh conveyors, wherein a perforated drum is immersed in a washing liquid, wherein the inner conveyor is disposed inside of the sliver sheet, and the outer conveyor is disposed outside of the sliver sheet, and wherein the washing of the sliver sheet comprises sucking a washing liquid in the perforated drum while conveying the sliver sheet along an outer periphery of the perforated drum, with the sliver sheet sandwiched between the inner mesh conveyor and the outer mesh conveyor, and passing the sucked washing liquid from outside of the outer conveyor through the outer mesh conveyor, then through the sliver sheet, then through the inner conveyor, and then through the perforated drum.

By rotating the sliver sheet along the periphery of the perforated drum while being sandwiched between the perforated conveying media, it is possible to make a washing liquid pass through the sheet surface of the sliver sheet without applying a force which causes separation of the sliver sheet, and it is possible to save the space for washing. Also, by creating a negative pressure due to suction of the washing liquid in the perforated drum, it is possible to suck the washing liquid from outside of the mesh conveyors sandwiching the sliver sheet to be rotated along the outer periphery of the perforated drum, thereby making it possible to wash the sliver sheet while generating a constant liquid flow. Also, by circulating a portion of the sucked washing liquid to the outside of the mesh conveyors in a water tank storing the perforated drum, it is possible to reduce the amount of consumed washing liquid. In a conventional general washing method, an object is washed by bending and lifting up the object for water replacement in washing tanks, and the washing efficiency depends on how many times the object is bent and lifted up, and the number of used washing machines. If such a conventional method is used, a large number of washing machines will be required, and also the sliver may be cut during processing in the bending and lifting up step. In contrast thereto, by adopting a suction type as described above, and washing the sliver sheet while being sandwiched between, and conveyed by, the conveying media, it is possible to further reduce the risk of sliver cutting. Also, while the above conventional washing method requires a large number of long and large washing machines, in the present invention, since the sliver sheet is moved along the perforated drum, it is possible to significantly shorten the space required for the water tank, and thus to significantly reduce the amount of consumed water and the size of a required factory site, compared to using the conventional method.

After the bleaching is finished, a function may be applied to the cotton material in the sliver state.

When applying functions to the fibers with various chemical agents, too, it is advantageous to do so in the sliver state, because this facilitates infiltration of the chemical liquids/agents and heating, and reduces the amount of consumed water resources, compared to applying functions in a hot water bath. The cotton sliver neutralized and washed with hot water after bleached is close to pure cellulose, and thus reacts quickly when applying a function thereto, thereby increasing work efficiency.

The sliver after bleached by the above method has been sufficiently whitened in the sliver state. By spinning this sliver, it is possible to obtain threads of which the individual fibers are sufficiently white. In a conventional method in which threads are first twisted, and then are refined and bleached, the inner portions of the threads are less likely to be effectively refined and bleached due to twisting; the threads need to be refined and bleached with a large amount of water; and thread portions which has not been sufficiently bleached tend to remain in the threads. For threads obtained from the sliver after refined and bleached according to the method of the present invention, since the threads have been refined and bleached without generating a disadvantage as described above caused by twisting, the individual fibers have been sufficiently processed, and thus the quality is good.

For the sliver of a cotton-containing material after bleached and refined according to the present invention, since the sliver has been already bleached and refined in the sliver state, it is possible to easily dye the sliver later. Also, since the sliver has been already refined, it is possible to easily obtain a textile product via various steps such as thread spinning, spinning and cloth weaving. At this time, since refining and bleaching, which tend to consume a large amount of water resources, have been already performed to the fibers in the sliver state, it is possible to significantly reduce the amount of water resources required for manufacturing cotton products. It is possible to obtain not only a 100% cotton product formed of threads spun from the above sliver, but also a cotton-containing product formed by blending together the above threads and threads made of a fiber other than cotton.

As a device for manufacturing a cotton-containing product by processing the sliver according to the present invention, a washing machine of a suction type may be used which comprises: a perforated drum immersed in a washing liquid; a suction device configured to suck the washing liquid from inside of the perforated drum; a pair of inner and outer mesh conveyors between which a sliver sheet is to be sandwiched; and a conveyor guiding device for conveying the sliver sheet along an outer periphery of the perforated drum, while sandwiching the sliver sheet between the inner mesh conveyor and the outer mesh conveyor, with the inner mesh conveyor disposed inside of the sliver sheet and the outer mesh conveyor disposed outside of the sliver sheet, wherein the suction device is configured to suck a washing liquid in the perforated drum, and pass the sucked washing liquid from outside of the outer mesh conveyor through the outer mesh conveyor, then through the sliver sheet, then through the inner conveyor, and then through the perforated drum, thereby washing the sliver sheet.

In other words, a production line for a cotton-containing product of a cotton material may be used wherein a refining step and a bleaching step are continuously performed on the cotton material, and wherein, in at least one of the refining step and the bleaching step, the production line includes: a steamer configured to heat a sliver sheet of the cotton material by applying steam to the sliver sheet after immersing the sliver sheet in a liquid; and the above-described washing machine of the suction type, which is configured to wash the sliver sheet after the heating.

Effects of the Invention

According to the present invention, it is possible to significantly reduce the amount of water resources required for manufacturing cotton-containing products; reduce a burden on the environment; and manufacture cotton-containing products in more areas.

Regarding conventional refining and bleaching of batch type, threads after spun are refined for about 30 minutes in a refining liquid such as a surfactant, an enzyme agent or an alkaline agent, and then are bleached for 60 to 90 minutes in the same bath with, e.g., a surfactant, caustic soda or hydrogen peroxide. If caustic soda is used for bleaching, a lot of water and strong neutralizing acid (sulfuric acid) are required for washing and neutralizing this high alkalinity. This increases the amount of discharged processing water, and increases the burden of discharged processing water due to the its quality deterioration. Also, strong acid tends to damage the device. Regarding refining and bleaching continuously performed to a sliver, the use of strong alkali is not required; bleaching reaction can be completed in about 3 to 8 minutes; and refining reaction can be completed in 5 minutes or less. Such a manufacturing method is excellent in that it also can reduce processing time. Also, such a manufacturing method can reduce the amount of energy required for heating water, and reduce even a factory space required for processing. As a result thereof, it is possible to construct a small textile factory of which the burden on the environment is small, even in areas where it was difficult to construct a textile factory, thereby making it possible to vitalize the textile industry.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart schematically illustrating the steps of a cotton-containing product manufacturing method according to the present invention.

FIG. 2A is a plan view of a system used in the cotton-containing product manufacturing method according to the present invention.

FIG. 2B is a front view of FIG. 2A.

FIG. 2C is a left side view of FIG. 2A.

FIG. 3A is a plan view of a washing machine used in an embodiment of the present invention.

FIG. 3B is a front view of FIG. 3A.

FIG. 3C is a left side view of FIG. 3A.

FIG. 4 is an enlarged front view of the washing machine used in the embodiment of the present invention.

FIG. 5 is a schematic diagram of the washing machine of suction type used in the embodiment of the present invention.

FIG. 6 is a photograph of a sliver sheer placed on a stainless steel net.

FIG. 7 is a flow chart schematically illustrating the steps of a different, cotton-containing product manufacturing method according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is described below in detail.

The present invention relates to a manufacturing method for manufacturing a cotton-containing product using a cotton material, and a cotton-containing product manufactured by this manufacturing method. The “cotton-containing product” refers to both a pure cotton product and a product containing cotton and another fiber. The present invention is particularly suitable for a pure cotton product.

The cotton material used in the present invention comprises a fiber or fibers including cotton. Not only a 100% cotton material but also blended and spun fibers comprising cotton and another fiber can be used. Specifically, such blended and spun materials include:

a cotton-and-Cannabis sativa-blended-and-spun material formed by blending and spinning cotton and Cannabis sativa such as ramie, linen or hemp;

a cotton-and-wool-blended-and-spun material formed by blending and spinning wool and cotton;

a cotton-and-cashmere-blended-and-spun material formed by blending and spinning cashmere and cotton;

a cotton-and-animal hair-blended-and-spun material formed by blending and spinning cotton and another animal hair;

a cotton-and-silk-blended-and-spun material formed by blending and spinning silk and cotton;

a cotton-and-regenerated cellulose fiber-blended-and-spun material formed by blending and spinning cotton and a regenerated cellulose fiber, e.g., lyocell such as Tencel (registered trademark), cupra (copper ammonia rayon), polynosic, rayon, or bamboo rayon; and

a cotton-and-synthetic fiber-blended-and-spun material formed by blending and spinning cotton and a synthetic fiber such as acetate fiber, nylon fiber or acrylic fiber.

In the present invention, a cotton material is processed in the state of a sliver, which is an aggregate of fibers before being twisted into threads. Specifically, the sliver is refined to remove dirt and oil components attached to the cotton, and bleached to whiten the brownish color. Basically, the bleaching is performed after the refining. Since the fibers are not sufficiently entangled in the sliver state, they will be disentangled when a strong force is applied thereto. Therefore, in the present invention, the sliver is preferably processed while being conveyed by a perforated conveying medium (or media) having holes. Such conveying perorated media include, e.g., a net, a group of chains, and a plate having holes in its plate surface. If a net is used, its meshes act as the holes. If a chain conveyor is used which comprises chains connected together on a plane, the holes of the individual rings, and the gaps between the respective rings act as the “holes”. As a plate having holes, for example, individual blocks constituting the conveyor and each having holes in its plate surface can be used, or a cylindrical plate constituting a cylindrical drum, and having holes in its peripheral surface can be used.

In the present invention, the slivers are processed while being placed on such a conveying medium. Instead of a single conveying medium, a plurality of conveying media may be used alternately, or the slivers may be sandwiched between a plurality of conveying media. When placing the slivers onto a conveying medium, the slivers are preferably arranged into sheets. The sliver arranged in a sheet shape is referred to as “sliver sheet”. By arranging the sliver in a sheet shape, it is possible to handle the sliver as a single aggregate due to the friction between the individual fibers constituting the sliver, thus enabling the sliver to have a strength required when conveyed and processed. This prevents separation of the individual fibers even when subjected to steam or a liquid flow as described later.

FIG. 1 shows a flow including a production line where the above cotton material is processed in the sliver state to obtain a cotton-containing product. The “cotton-containing product” is a product comprising a fiber or fibers including cotton as with the above cotton material, and such “products” include not only a product of a 100% cotton material but also a product of blended and spun fibers comprising cotton and another fiber. Specifically, examples of the above products include, e.g., spun threads, woven fabrics produced from threads, and clothes, towels and other practical products that are made from woven fabrics. FIG. 1 exemplifies steps to obtain threads as the above product.

First, the sliver is taken out of a supply source 11, and arranged in a sheet shape to form a sliver sheet. In terms of work efficiency, the sliver sheet is preferably a seamless, continuous sheet. The sliver sheet formed by arranging the sliver in this way is continuously placed onto the above conveying medium, and refined in a refining step 12. In the refining step 12, foreign objects included in the raw cotton, such as plant leaves and stems, and other undesired objects such oils and fats, and other impurities, are removed before the next bleaching step 13. After the refining step 12, the sliver sheet is sequentially introduced into the bleaching step 13 as it is. In the bleaching step 13, color components which look yellow or brown mainly derived from the original color of the cotton are removed to whiten the fibers. After the bleaching step 13, a post-processing step 14 is, if necessary, performed, and a bleached sliver of which the individual fibers have been refined and bleached thoroughly is obtained. After a spinning step 15 where the bleached slivers are spun, threads are obtained as the cotton product.

As the above sliver supply source, the Kens method may be used or the wrapping method may be used. Also, in the first place, the sliver per se is obtained by arraying and bundling raw cotton by use of a carding machine. The sliver bundled in a strap shape may be developed into a sheet shape later, or the sliver may be developed into a sheet shape from the beginning. Fibers bundled together to constitute a continuous sliver of cotton material are developed into a sheet shape within the width range of the conveying medium located within the widths of the machines used in the subsequent steps, thereby sequentially forming the continuous sliver sheet. The sequentially formed continuous sliver sheet is then sequentially processed in the above-described steps. In order to assist in this conveyance of the continuous sheet, the forming speed at which the continuous sliver sheet is formed needs to be equal to, or faster than, the processing speeds in the subsequent steps. However, since the sliver or the sliver sheet needs to be pulled until it is placed onto the conveying medium, it is necessary to adjust the tensile load so as to prevent disentanglement of the slivers.

An exemplary production line where the refining step 12 to the post-processing step 14 are continuously performed on the continuous sliver sheet is shown in the plan view of FIG. 2A, the front view of FIG. 2B, and the side view of FIG. 2C when seen from the side of a refining padder 21. These steps are sequentially performed from left to right in FIGS. 2A and 2B.

First, the refining step 12 is described. In the refining padder 21, a liquid immersion sub-step 12 a is perform as a preparation part of the refining step 12. The refining padder 21 is configured to receive the continuous sheet-shaped sliver sheet 51 on an inwardly inclined receiving seat located at a lower portion of its injection port. The refining padder 21 is further configured to send the continuous sliver sheet 51 received on the receiving seat to a refining liquid immersion portion 21 a. When sending the sliver sheet into the portion 21 a, and feeding it within the devices, a conveying medium such as a mesh conveyor is used which can convey the continuous sliver sheet 51 while being placed on the conveying medium. The refining padder 21 is further configured to squeeze, in a pressure applying mangle device 21 b, the continuous sliver sheet to which a refining liquid was applied at the refining liquid immersion portion 21 a, and then feed it out of the refining padder 21. The liquid immersion sub-step 12 a does not particularly require heating, and can be performed at normal temperature (room temperature). The refining liquid is stored in the refining liquid immersion portion 21 a, and the continuous sliver sheet 51 is immersed in the refining liquid at a speed of, approximately, not less than 5 m/minute to 10 m/minute. In a general refining step for refining threads, about four to five liquid tanks for storing a refining liquid are prepared, and threads are continuously immersed in these liquid tanks to infiltrate the refining liquid into the fibers, or threads are processed for a long time with a high-temperature chemical liquid. This is because cotton fibers are covered with oil and fat, or pectin, and thus water-repellent, i.e., do not absorb water. In contrast, in the present invention, since the continuous sliver sheet 51 is immersed in the refining liquid, and the individual fibers are entangled weakly in this state, even though the continuous sliver sheet is water-repellent, it is possible to sufficiently infiltrate the refining liquid into the individual fibers by immersing the sliver sheet only once.

The above refining liquid has weak acidity, and preferably has a pH of about not less than 3.0 and not more than 5.5. The above refining liquid preferably contains, in addition to the acid components, an acid-resistant penetrant, an enzyme catalytic agent, a degassing penetrant, etc. The enzyme catalytic agent is a chemical agent enabling effective refining under the high-temperature conditions in the next steam heating sub-step 12 b. The degassing penetrant promotes replacement of air contained in the slivers with the refining liquid. Since the degassing penetrant quickens infiltration, by using the degassing penetrant, it is possible to omit, for example, a pre-washing tank and a chemical application tank, and thus to reduce the amount of water required for the processing.

The roll-squeezing conditions of the pressure applying mangle device 21 b, which is located on the exit side of the liquid immersion sub-step 12 a, are preferably about 70 to 100%. However, the continuous sliver sheet needs to be kept wet to some extent. In a wet state, the continuous sliver sheer has a strength enough to be able to maintain its shape in the subsequent processing, too, due to the friction between the individual fibers. Preferably, the sliver sheet is conveyed by the above conveying medium until immediately before being sandwiched between the upper and lower rolls, and conveyed again on the same conveying medium right after being squeezed by the rolls.

Next, in a refining steamer 22, the steam heating sub-step 12 b is performed to heat the continuous sliver sheet 51 to which the refining liquid has been applied. Refining reaction is advanced by steam filling the interior of a steamer tank into which the continuous sliver sheet 51 with the refining liquid is sent. The temperature of the interior of the steamer tank 22 a is preferably about not less than 98° C. and not more than 105° C. If this temperature is too low, the steam will condense, so that heat transfer may be insufficient. On the other hand, if the above temperature is too high, an unexpected reaction may occur. The reaction time in the steamer tank is preferably about not less than 1 minute and not more than 5 minutes. The steam pressure of the introduced steam is preferably about not less than 0.3 MPa and not more than 0.7 MPa. Since the continuous sliver sheet 51 has been squeezed by the pressure applying mangle device 21 b, although the surface of the continuous sliver sheet 51 is wet, little water is present on the surface. Therefore, molecules of steam, which are sufficiently smaller than liquid waterdrops, easily come into contact with the individual fibers, and quickly supplies a sufficient amount of heat to heat the fibers, thereby making it possible to advance the refining reaction in a short time. In order to easily apply steam to the entire continuous sliver sheet 51, the conveying medium for conveying the sliver sheet 51 preferably has holes through which steam passes, as with a mesh conveyor.

Next, in a washing machine 23, a washing sub-step 12 c is performed to wash off the refining liquid that remains adhered to the continuous sliver sheet 51 after the reaction.

Preferably, the continuous sliver sheet 51 is washed in the washing machine 23, while being conveyed by a conveying medium having holes. If individual sliver sheets are independently immersed in a washing liquid, they could be disentangled. However, by placing the continuous sliver sheet on a conveying medium having holes, or by sandwiching the sheet 51 between conveying media having holes, it is possible to continuously wash a large amount of sliver while preventing disentanglement of, and damage to, the slivers.

Especially in order to continuously wash the continuous sliver sheet 51 without damaging the sliver sheet 51, by using inner and outer mesh conveyors 53 a and 53 b as the conveying media having holes; and immersing the continuous sliver sheet 51 in the liquid, thus exposing the sliver sheet 51 to a liquid flow, with the sliver sheet 51 sandwiched between the inner and outer conveyors 53 a and 53 b, it is possible to wash the continuous sliver sheet 51 while protecting the sliver sheet 51 by the conveyors on both sides thereof.

As the washing machine 23, a normal washing machine can be practically used. However, by using a washing machine 50 of the liquid suction type, it is possible to maximize the advantage of washing the fibers in the form of the continuous sliver sheet 51. A single washing machine of the liquid suction type can produce a washing effect roughly comparable to the washing effect of three to four general washing machines of the replacement type. Since the individual fibers of the continuous sliver sheet 51 are not twisted together, it is possible to wash the individual fibers quickly by liquid suction. Also, by liquid suction, it is possible to wash the sliver sheet with a small amount of washing liquid, compared to washing in a static liquid, and thus to reduce the amount of water used. In a conventional arrangement in which threads or fabrics are continuously washed in a static liquid, a long and large tank is required for washing. By using the washing machine 50 according to the present invention, it is possible to use a compact tank, and realize an energy-saving factory, i.e., significantly reduce both the consumption of water and the area of land occupied.

The washing machine 50 of the liquid suction type includes a perforated drum 57 having holes and immersed in a washing liquid; and a suction device for sucking the washing liquid from inside of the perforated drum 57. The washing machine 50 further includes a conveyor guiding device for conveying the continuous sliver sheet 51 along the outer periphery of the perforated drum 57 with the continuous sliver sheet 51 sandwiched between the inner conveyor 53 a located inside of the continuous sliver sheet 51 and the outer conveyor 53 b located outside of the continuous sliver sheet 51.

The washing machine 50 of the suction type, which includes the above-described suction device and conveyor guiding device, is now described while exemplifying its specific embodiment. FIGS. 3A, 3B and 3C show, respectively, a plan view, a front view and a left side view of the embodiment. FIG. 4 shows an enlarged view of the perforated drum 57, located at the center of the front view, and its vicinity. FIG. 5 schematically illustrates the perforated drum 57 in the above views, and its vicinity.

The continuous sliver sheet 51 is introduced into the washing machine 50 while being placed on a conveying medium or media. In the embodiment, conveying media comprising two chain conveyors (inner and outer conveyors 53 a and 53 b) are used. After washing the continuous sliver sheet 51 while being sandwiched between the inner and outer conveyors 53 a and 53 b, the continuous sliver sheet 51 is fed while being placed on the outer conveyor 53 b to a pressure applying mangle device 52 and squeezed by the mangle device 52 to remove excess liquid. FIG. 6 is a photograph of the continuous sliver sheet 51 when discharged from the pressure applying mangle device 52, received by another chain conveyor 53 c, and fed to the next step.

The continuous sliver sheet 51 conveyed from the upper left side of FIG. 4 is introduced into washing water in a washing tank 54, while being sandwiched between a portion of the outer conveyor 53 b that is moving from the lower side, and a portion of the inner conveyor 53 a that is moving from the upper side. The inner and outer conveyors 53 a and 53 b, and the continuous sliver sheet 51 sandwiched between these conveyors are introduced into the washing water so as to be moved along the outer periphery of the perforated drum 57, which is immersed in washing water in the washing tank 54, with the outer conveyor 53 b facing outward. The perforated drum 57 has a cylindrical shape, and is formed with a plurality of holes sufficient in number and size to such an extent that a sufficient amount of washing water for washing the continuous sliver sheet 51 can be supplied through these holes.

The above conveyor guiding device is configured to guide the conveyors such that the continuous sliver sheet 51 is continuously conveyed along the outer periphery of the perforated drum 57. The conveyor guiding device is constituted by a plurality of rollers, described later, which are disposed such that (i) the continuous sliver sheet 51 is sandwiched between a portion of the inner conveyor 53 a and a portion of the outer conveyors 53 b; (ii) the portions of the inner and outer conveyors between which the sliver sheet is not sandwiched are continuously moved; and (iii) the inner and outer conveyors and the sliver sheet are guided along the outer periphery of the perforated drum 57. Conveyor driving devices for driving the respective conveyors per se are preferably connected to some of these rollers.

The inner conveyor 53 a moves along a loop path at the upper central portion of FIG. 4 as follows: The moving direction of the inner conveyor 53 a is changed to a downward direction by a roller 72 b, and the inner conveyor 53 a is moved in a right and downward direction in FIG. 5, while forming a three-layer structure in which the continuous sliver sheet 51 is sandwiched between the inner conveyor 53 a and the outer conveyor 53 b, which is being fed from the lower side. The moving direction of the inner conveyor 53 a is then changed to a left and downward direction in FIG. 5 by a roller 56 b to which the inner conveyor 53 a is hooked, and the inner conveyor 53 a is moved substantially completely around the outer periphery of the perforated drum 57. At this time, while the inner conveyor 53 a comes into contact with the outer periphery of the perforated drum 57, because the continuous sliver sheet 51 is moved on the outer side of the inner conveyor 53 a, it does not come into contact with the perforated drum 57. After the inner conveyor 53 a is moved away from the perforated drum 57 while maintaining the three-layer structure, the moving direction of the inner conveyor 53 a is changed to a right and upward direction in FIG. 5 by a roller 56 a. When the moving angle of the outer conveyor 53 b is changed by a roller 71 a, the continuous sliver sheet 51, supported on the outer conveyor 53 b, follows the outer conveyor 53 b, and is separated from the inner conveyor 53 a. The moving direction of the inner conveyor 53 a is changed again by a roller 72 a, and the inner conveyor 53 a moves past a tension roller 73 a of a tensioner 70 a and reaches the roller 72 b again. The tensioner 70 a presses the inner conveyor 53 a from above, thereby applying a force such that the inner conveyor is moved without loosening. The position where the tensioner 70 a is disposed is not limited to the position shown, but the tensioner is preferably disposed at a position where the tensioner does not overlap with the continuous sliver sheet 51. This is because, if the tensioner is disposed at a position where the tensioner overlaps with the sliver sheet, excess tension will be applied to the continuous sliver sheet 51, and this may damage the sliver.

The conveyor driving device for driving the inner conveyor 53 a per se is configured such that the roller 72 a is rotated by a driving roller 68 rotated by a motor 66 via a chain 69, thereby causing the entire inner conveyor 53 a to move along a loop path. The roller 72 a is not limited to the roller shown. By the mechanism for driving the inner conveyor 53 a, and the below-described mechanism for driving the outer conveyor 53 b, the continuous sliver sheet 51 sandwiched between the inner conveyor 53 a and the outer conveyor 53 b is rotated along the outer periphery of the perforated drum 57.

On the other hand, the outer conveyor 53 b moves along a loop path extending inside and outside of the washing tank 54 as follows: The outer conveyor 53 b is moved from the left in FIG. 5; the moving angle of the outer conveyor 53 b is changed to a right and downward direction in FIG. 5 by a roller 71 j; and the outer conveyor 53 b is moved in the right and downward direction, while forming a three-layer structure in which the continuous sliver sheet 51 is sandwiched between the outer conveyor 53 b and the inner conveyor 53 a, which is moving from the upper side. Next, the moving direction of the outer conveyor 53 b is changed by the roller 56 b, and the outer conveyor 53 b is moved substantially completely around the perforated drum 57 as with the inner conveyor described above. At this time, the inner conveyor 53 is located on the inner side of the sliver sheet while being kept in contact with the perforated drum 57, and the outer conveyor 53 b is moved on the outer side of the sliver sheet, with the continuous sliver sheet 51 sandwiched between these conveyors. The moving direction of the outer conveyor 53 b is then changed to a right and upward direction in FIG. 5 by the roller 56 a, and the moving direction of the outer conveyor 53 b is further changed to a less steep inclination angle by the roller 71 a. As a result, the continuous sliver sheet 51 is separated from the inner conveyor 53 a, and fed to the contact point of two rollers constituting the pressure applying mangle device 52, while being placed on the outer conveyor 53 b. The moving direction of the outer conveyor 53 b is changed to a downward/opposite direction by a roller 71 b disposed before the contact point of the above two rollers. T moving direction of the outer conveyor 53 b is further changed by a roller 71 c, then by a roller 71 b, and then by a roller 71 e, and further changed by a roller 71 f located below the washing tank 54 such that the outer conveyor 53 b is fed in the left direction in FIG. 4 under the bottom of the washing tank 54. The moving direction of the outer conveyor 53 b is then changed to the upward direction by rollers 71 g and 71 h, and further changed to a substantially horizontal direction by a roller 71 i. The outer conveyor 53 b then moves past a tension roller 73 b of a tensioner 70 b, and reaches the roller 71 j. Then, the outer conveyor 53 b again moves along the above-described loop path, while forming the three-layer structure. The tensioner 70 b also presses the outer conveyor 53 b from above, thereby applying a force such that the outer conveyor is moved without loosening. As with the tensioner for the inner conveyor 53 a, the position where the tensioner 70 b is disposed is not limited to the position shown, but the tensioner 70 b is preferably disposed at a position where the tensioner 70 b does not overlap with the continuous sliver sheet 51.

The conveyor driving device for driving the outer conveyor 53 b per se is configured such that the roller 71 d is rotated by the driving roller 68, which is rotated by the motor 66 via the chain 69, thereby causing the entire outer conveyor 53 b to move along the loop path. The roller 71 d is not limited to the roller shown.

The continuous sliver sheet 51 is conveyed along the outer periphery of the perforated drum 57, while being sandwiched between the inner and outer conveyors 53 a and 53 b. By conveying the sliver sheet while being sandwiched between these conveyors, it is possible to reduce the possibility of the sliver being severed due to frictional resistance, contact resistance, etc. By introducing and discharging the continuous sliver sheet 51 while being sandwiched between the conveyors and rotated, the sliver, having a low specific gravity and likely to float in the processing liquid, can be sequentially submerged in the liquid, thus preventing cloth floating and improving infiltration of the liquid.

The inner and outer conveyors 53 a and 53 b are conveying media having holes through which a liquid flow can pass. The perforated drum 57, along which these conveyors are guided, also has, in its circumference, a plurality of holes through which a liquid flow can pass. Since the individual fibers of the continuous sliver sheet 51 are not twisted together, the continuous sliver sheet 51 per se has a structure in which the individual fibers are easily exposed to the liquid flow. The perforated drum 57 has a suction port 59 through which washing water is axially sucked from inside of the perforated drum 57 near its center. When washing liquid is sucked through the suction port 59 by the suction device, a negative pressure is generated in the interior of the perforated drum 57, and thus liquid in the washing tank 54 is sucked into the perforated drum 57, while passing through the outer conveyor 53 b, the continuous sliver sheet 51, the inner conveyor 53 a, and the perforated drum 57. By being exposed to this liquid flow, the continuous sliver sheet 51 is washed quickly. Since the continuous sliver sheet 51 is moved by the conveyors while being sandwiched therebetween, its displacement or contact movement does not occur. Therefore, it is possible to efficiently perform liquid replacement in the fibers, and thus to wash the sliver sheet extremely efficiently, compared to doing so in a simple washing machine.

After washing, the continuous sliver sheet 51 is squeezed by the pressure applying mangle device 52 so as to remove water, and then conveyed to the next step while being placed on the chain conveyor 53 c.

Since water in the washing tank 54 is continuously discharged out of the system while being carried by the continuous sliver sheet 51, it is desirable to supply water into the tank 54 as necessary. Specifically, water sucked through the axially extending suction port 59 at the center of the perforated drum 57 is introduced into a pump 63 through a downwardly extending suction pipe 62. The pump 63 constitutes the suction device configured to suck water from inside of the perforated drum 57. The water is fed from the pump 63 into an upwardly extending discharge pipe 64, and is returned into the washing tank 54 from a spout 65 disposed above a predetermined water level, through the discharge pipe 64. On the other hand, the washed continuous sliver sheet 51 is fed into the next bleaching step 13 after removing excess water with the pressure applying mangle device 52 near the exit.

Next, the bleaching step 13 is described. In a bleaching padder 31, a liquid immersion sub-step 13 a is performed as a preparation part of the bleaching step 13. The basic structure of the bleaching padder 31, and the basic system thereof comprising a bleaching liquid immersion portion 31 a and a pressure applying mangle device 31 b are the same as those of the above refining padder 21, in which the liquid immersion sub-step 12 a is performed, and a bleaching liquid is adhered to the continuous sliver sheet 51 in the liquid immersion sub-step 13 a. However, the bleaching liquid used here is different from the above refining liquid.

The above bleaching liquid is an alkaline liquid containing a bleaching agent, and preferably has a pH of about not less than 8.5 and not more than 11.0. Hydrogen peroxide water can be suitably used as the bleaching agent. The bleaching liquid preferably contains a penetrant which promotes wetting, because such a penetrant quickens infiltration of the chemical liquid, so that it is possible to omit, e.g., a pre-washing tank and/or a chemical liquid application tank, and thus to reduce the amount of water required for the processing. Further preferably, the bleaching liquid contains a hydrogen stabilizer and/or a reaction catalyst. As an alkaline agent for alkalinizing the bleaching liquid, for example, a chemical agent that shows weak alkalinity such as sodium carbonate can be suitably used.

The roll-squeezing conditions of the pressure applying mangle device 31 b on the exit side of the liquid immersion sub-step 13 a are preferably about 70 to 100%. However, the sliver sheet needs to be kept wet to some extent. In a wet state, the continuous sliver sheet has a strength enough to be able to maintain its shape in the subsequent processing, too, due to the friction between the individual fibers.

Next, in a bleaching steamer 32, a steam heating sub-step 13 b is performed to heat, with steam in a steamer tank 32 a, the continuous sliver sheet to which the bleaching liquid has been applied. The process in the steamer tank 32 a can be performed under conditions similar to those of the process in the above steamer tank 22 a. With the bleaching liquid applied, the continuous sliver sheet is fed into the steamer tank, and subjected to bleaching reaction by steam filling the interior of the steamer tank. While the reaction generated by the heated bleaching liquid is different from the reaction generated in the refining step 12, it is preferable that the structure and conditions of the device are basically the same as those of the corresponding device in the refining step 12. However, the reaction time in the tank of the bleaching steamer 32 is preferably about not less than 6 minutes and not more than 8 minutes. This reaction time is longer than the reaction time in the refining step, but can be significantly reduced to at most half or less, and in some cases to one-fourth or less, of the reaction time when conventional bleaching is performed in a hot water bath. Therefore, compared to conventional methods, it is possible to significantly reduce the consumption of energy or water required for bleaching which requires a processing load larger than refining requires.

Next, in a washing machine 33, a washing sub-step 13 c is performed to wash off the bleaching liquid that remains adhered to the continuous sliver sheet after the reaction. By using a washing machine 50 of the suction type as in the above washing sub-step 12 c, it is possible to quickly wash off the bleaching liquid without damaging the continuous sliver sheet 51, while reducing the amount of water required for washing.

Thereafter, the post-processing step 14 is performed. First, a neutralization sub-step 14 a is performed in a neutralization paddler 41. Specifically, since the continuous sliver sheet 51 still has alkalinity due to the bleaching liquid even after the washing following the bleaching, the sheet 51 is neutralized in this sub-step. Thereafter, a hot washing sub-step 14 b is performed in a hot water washing shower padder 42 to complete the sliver sheet.

During the post-processing step, or before or after the post-processing step, other function processes may be performed, such as a durability/softening process, a washing durability process, an antibacterial process, a quick-drying function process, a sweaty odor eliminating process, an aging odor eliminating process, and/or a water-repellent process. FIG. 7 shows an exemplary flow in which a function applying step 17 is performed after the post-processing step. The steps shown here other than the function applying process 17 are the same as the steps shown in FIG. 1. In a liquid immersion sub-step 17 a of the function applying step 17, the sliver sheet is immersed in a chemical liquid corresponding to the functions to be applied. For example, in the liquid immersion sub-step 17 a, chemical liquids each corresponding to one of the above-exemplified function processes are used. Alternatively, chemical liquids each corresponding to two or more of the above processes may be used. After being processed in the neutralization sub-step 14 a and the hot washing sub-step 14 b of the post-processing step 14, the sliver is neutralized, and thus can be easily handled, and impurities have been removed from the sliver, thus enabling chemical liquids for processing to easily react with the sliver. Also, since the fibers to be processed are in the sliver state, chemical liquids for function processes infiltrate into the sliver quickly and suitably without being interrupted by the individual fibers, thereby making it possible to apply an effect to the sliver. Thereafter, in a drying sub-step 17 b, liquid components are removed, thereby making it possible to obtain a sliver which produces a high effect. By, in the spinning step 15, spinning this sliver into threads, it is possible to obtain a cotton product in which the expected functions are suitably applied to the individual fibers. Thus, it is possible to significantly reduce not only the consumption of water and energy required for the function processes, but also the space required for these processes, compared to conventional methods in which these functions are applied to threads or fabrics.

Thereafter, though not shown, the sliver is preferably dried in the form of the continuous sliver sheet 51. In a wet state, the sliver sheet has a certain degree of strength due to increased frictional forces between the fibers, but this strength decreases after drying. Therefore, the sliver sheet is preferably dried while being placed on a conveying medium having holes. The dryer used for drying preferably has a structure which can prevent excessive dispersion of liquid due to the air volume, wind speed and wind pressure during drying. Hot air is blown out from the interior of the dryer to the upper and lower sides of the dried object. The wind outlet of the dryer preferably has a structure which allows hot air to easily pass through the gaps between the fibers of the continuous sliver sheet. The heat source required for drying may be steam, gas or an electric heater. It is preferable that the temperature of applied heat can be selectively changed between 70° C. and 180° C., depending on the material of cotton to be dried. As a result of fully drying the continuous sliver sheet, by the function of the dryer which can control wind pressure and wind volume, it is possible to obtain a continuous sliver sheet bulging like the shape of the continuous sliver sheet when injected.

In this way, it is possible obtain a bleached sliver, or a sliver to which the above functions have been applied by additional function processes. The obtained continuous sliver sheet is spun into threads (spinning step 15) after being formed into the shape of KGY slivers having a thickness of about 1 KGY. In order to form the continuous sliver sheet into the KGY slivers, either one of the following first and second methods may be selected. In the first method, as in a normal, raw cotton spinning step, the sliver sheet is processed in a blending and blowing machine, and then processed in a drawing frame via. e.g., a carding machine, thereby obtaining the KGY slivers for spinning. In the second method, individual slivers separated from the sliver sheet and each distributed as a single sliver are injected into a drawing frame as they are, thereby obtaining the KGY slivers for spinning. The KGY slivers formed by either of the first and second methods can be spun at a desired thickness into threads having a function according to the desired thickness. In the first method, more manufacturing steps and more time are required, thus increasing the cost. On the other hand, in the second method, since the processed slivers can be injected into a drawing frame as they are, it is possible to obtain spun threads in a short time without increasing the cost, and thus to streamline production. In the second method, since the sheet-shaped sliver after dried needs to be separated into the individual slivers by a sliver separating device, this device is preferably prepared beforehand as a sliver separating and distributing device so as to be additionally usable when required later.

In order to obtain a woven fabric and a practical product, after the steps in FIG. 1, the step of combining threads together to obtain a fabric or fabrics, and the step of forming the fabric(s) into a predetermined shape by cutting, sewing, etc. are added.

EXAMPLES

Examples are described below in which refining and bleaching of slivers using steam according to the present invention were actually performed. Whiteness degree was evaluated using JIS whiteness degree and Hunter whiteness degree, and measured using a CR410 colorimeter of Konica Minolta. The results are shown in the following Table 1.

TABLE 1 Refining method L* a* b* JIS value L a b Hunter value Example 1 Refining with no 96.06 −1.43 2.49 84.3 94.95 −1.45 2.44 94.21 degassing penetrant Example 2 Refining with 96.2 −1.4 2.37 84.89 95.13 −1.38 2.42 94.39 degassing penetrant Comparative Batch refining, steam 95.78 −1.45 2.95 82.58 94.66 −1.46 2.88 93.76 Example 1 bleaching

Examples 1 and 2

In the refining step using steam, refining was performed with refining liquids each containing chemical agents as shown in the below-inserted Table 2. These chemical agents are acid refining agent—chemist DN (produced by Satoda Chemical Industrial Co., Ltd.); acid-resistant penetrant—anizol MA-27 (produced by Satoda Chemical Industrial Co., Ltd.); enzyme catalytic agent—AC600 (produced by RAKUTO KASEI INDUSTRIAL CO., LTD.); and degassing penetrant—MAC-N2 (produced by Hokko Chemical Co., Ltd.). After the corresponding refining liquid was applied to each sliver by the refining padder at normal temperature, the sliver was treated with steam of 100° C. for 3 minutes, and washed by the washing machine of the suction type shown in FIGS. 3A to 3C and FIG. 4. Thereafter, the sliver was bleached as described below.

TABLE 2 Comparative Used chemical agent Example 1 Example 2 Example 1 Acid refining agent-Chemist DN 1.2 g/L 1.2 g/L 1.5 g/L Penetrant-anizol MA27 5.0 g/L 5.0 g/L 2.0 g/L Enzyme catalytic agent-AC600 5.0 g/L 5.0 g/L 5.0 g/L Degassing penetrant-MAC-N2 nil 5.0 g/L — ph 4.5 5.0

Comparative Example 1

Batch refining was performed by immersion in a refining liquid. Specifically, an oven backet made of stainless steel to be placed into the cheese dyeing machine produced as a processing machine by HISAKA WORKS, LTD. and described in Japanese Patent No. 554172 was prepared, and a sliver was placed into this oven backet, and processed/treated for 30 minutes at a liquid temperature of 50° C. After washing the sliver, the sliver was bleached with steam, by use of the same chemical agents, and under the same condition, as used in bleaching in Example 1.

Examples 1 and 2, Comparative Example 1: Bleaching

In both the Examples and the Comparative Example, bleaching was performed with steam. Specifically, a bleaching liquid was applied to the bleaching padder, and each sliver was treated for 3 minutes with steam of 100° C. Then, after squeezing the beaching liquid out from the sliver by use of the pressure applying mangle device on the exit side, the sliver was washed by the washing machine of the suction type shown in FIGS. 3A to 3C and FIG. 4, and the sliver was neutralized and washed with hot water. The bleaching liquid contains chemical agents as shown in the below-inserted Table 3. These chemical agents are bleaching agent—hydrogen peroxide 35% (produced by ADEKA); penetrant—MAC-25S (produced by Hokko Chemical Co., Ltd.); stabilizer—Hokutol 110 (produced by Hokko Chemical Co., Ltd.); stabilizer—Neolate PL-3 (produced by NICCA CHEMICAL CO., LTD.); reaction catalyst—Catalyst OX (produced by Satoda Chemical Industrial Co., Ltd.); and alkaline agent—sodium carbonate (soda ash) (produced by Tokuyama). The pH was 10.3.

TABLE 3 Bleaching agent-hydrogen peroxide 35% 80.0 g/L Penetrant-MAC-25S 10.0 g/L Stabilizer-Hokutol 110 10.0 g/L Stabilizer-Neolate PL-3 20.0 g/L Reaction catalyst-Catalyst OX 30.0 g/L Alkaline agent-sodium carbonate 15.0 g/L

The treatment time in steam refining was 3 minutes, whereas the treatment time in batch refining was 30 minutes. In steam refining, the amount of required treatment liquid is substantially equal to the amount of each processed sliver, whereas, in batch refining, the amount of required treatment liquid is about 10 times larger than the amount of the processed sliver. While, compared to steam refining, a lot of treatment time is required, and a large amount of processing liquid is discharged in batch refining, by using the present invention, it is possible to reduce the treatment time and the amount of discharged water, and thus to reduce required energy, a burden on the environment, etc. Also, the whiteness degree of each sliver refined with steam is higher than that of the sliver refined in batch form, and the whiteness degree of the sliver refined with steam using the degassing penetrant is higher than that of the sliver refined with steam without using the degassing penetrant, thus improving its actual quality, too.

DESCRIPTION OF REFERENCE NUMERALS

-   11: Supply source -   12: Refining step -   12 a: Liquid immersion sub-step -   12 b: Steam heating sub-step -   12 c: Washing sub-step -   13: Bleaching step -   13 a: Liquid immersion sub-step -   13 b: Steam heating sub-step -   13 c: Washing sub-step -   14: Post-processing step -   14 a: Neutralization sub-step -   14 b: Hot washing sub-step -   15: Spinning step -   17: Function applying step -   17 a: Liquid immersion sub-step -   17 b: drying sub-step -   21: Refining padder -   21 a: Refining liquid immersion portion -   21 b: Pressure applying mangle device -   22: Refining steamer -   22 a: Steamer tank -   23: washing machine -   31: Bleaching padder -   31 a: Bleaching liquid immersion portion -   31 b: Pressure applying mangle device -   32: Bleaching steamer -   32 a: Steamer tank -   33: Washing machine -   41: Neutralization paddler -   42: Hot washing shower padder -   50: Washing machine -   51: Continuous sliver sheet -   52: Pressure applying mangle device 52 -   53 a: Inner conveyor -   53 b: Outer conveyor -   53 c: Chain conveyor -   54: washing tank -   56 a, 56 b: roller -   57: Perforated drum -   59: Suction port -   60: Overflow -   62: Suction pipe -   63: Pump -   64: Discharge pipe -   65: Spout -   66: Motor -   68: Driving roller -   69: Chain -   70 a, 70 b: Tensioner -   71 a to 71 i: Roller (for the outer conveyor) -   72 a, 72 b: Roller (for the inner conveyor) -   73 a, 73 b: Tension roller 

1. A manufacturing method for manufacturing a cotton-containing product of a cotton material, comprising refining and bleaching the cotton material in a state of a sliver, wherein, when the refining and the bleaching are each performed, heating is performed, with steam, on the cotton material with a chemical agent applied to the cotton material, and wherein, when the heating is performed, the steam is applied to the cotton material in a state of a sliver sheet formed by arranging the sliver in a sheet shape.
 2. (canceled)
 3. (canceled)
 4. The manufacturing method according to claim 1, further comprising, after the sliver sheet is heated by applying the steam to the sliver sheet, washing the sliver sheet while the sliver sheet is being conveyed by at least one perforated conveying medium.
 5. The manufacturing method according to claim 4, wherein the at least one perforated conveying medium comprises two perforated conveying media comprising inner and outer mesh conveyors, wherein a perforated drum is immersed in a washing liquid, wherein the inner conveyor is disposed inside of the sliver sheet, and the outer conveyor is disposed outside of the sliver sheet, and wherein the washing of the sliver sheet comprises sucking a washing liquid in the perforated drum while conveying the sliver sheet along an outer periphery of the perforated drum, with the sliver sheet sandwiched between the inner mesh conveyor and the outer mesh conveyor, and passing the sucked washing liquid from outside of the outer conveyor through the outer mesh conveyor, then through the sliver sheet, then through the inner conveyor, and then through the perforated drum.
 6. The manufacturing method according to claim 1, wherein, after the bleaching is finished, a function is applied to the cotton material in the state of the sliver.
 7. The manufacturing method according to claim 1, wherein after the bleaching, the sliver is spun into thread.
 8. (canceled)
 9. (canceled)
 10. A washing machine of a suction type comprising: a perforated drum immersed in a washing liquid; a suction device configured to suck the washing liquid from inside of the perforated drum; a pair of inner and outer mesh conveyors between which a sliver sheet is to be sandwiched; and a conveyor guiding device for conveying the sliver sheet along an outer periphery of the perforated drum, while sandwiching the sliver sheet between the inner mesh conveyor and the outer mesh conveyor, with the inner mesh conveyor disposed inside of the sliver sheet and the outer mesh conveyor disposed outside of the sliver sheet, wherein the suction device is configured to suck a washing liquid in the perforated drum, and pass the sucked washing liquid from outside of the outer mesh conveyor through the outer mesh conveyor, then through the sliver sheet, then through the inner conveyor, and then through the perforated drum, thereby washing the sliver sheet.
 11. A production line for a cotton-containing product of a cotton material, wherein a refining step and a bleaching step are continuously performed on the cotton material, and wherein, in at least one of the refining step and the bleaching step, the production line includes: a steamer configured to heat a sliver sheet of the cotton material by applying steam to the sliver sheet after immersing the sliver sheet in a liquid; and the washing machine of the suction type according to claim 10, which is configured to wash the sliver sheet after the heating.
 12. The manufacturing method according to claim 4, wherein, after the bleaching is finished, a function is applied to the cotton material in the state of the sliver.
 13. The manufacturing method according to claim 5, wherein, after the bleaching is finished, a function is applied to the cotton material in the state of the sliver.
 14. The manufacturing method according to claim 4, wherein after the bleaching, the sliver is spun into thread.
 15. The manufacturing method according to claim 5, wherein after the bleaching, the sliver is spun into thread.
 16. The manufacturing method according to claim 12, wherein after the bleaching, the sliver is spun into thread.
 17. The manufacturing method according to claim 13, wherein after the bleaching, the sliver is spun into thread.
 18. A production line for a cotton-containing product of a cotton material, wherein a refining step and a bleaching step are continuously performed on the cotton material, and wherein, in at least one of the refining step and the bleaching step, the production line includes a steamer configured to heat a sliver sheet of the cotton material by applying steam to the sliver sheet after immersing the sliver sheet in a liquid. 